I. Field of the Invention
The present invention relates generally to dental air abrasive systems for removing and/or cutting tooth structure, amalgam, composites, other dental tooth filling materials and/or stain.
II Description of the Prior Art
There are a number of previously known air abrasive systems which have been used in dentistry for cutting tooth structure, such as enamel and dentin. These previously known air abrasive systems typically comprise an elongated tube having a nozzle at one end and having its other end coupled through a valve to a source of compressed air. Additionally, a hopper containing abrasive particles, such as aluminum oxide, are fed into the fluid passageway between the compressed air source and the nozzle. Thus, with the valve open, the compressed air creates an abrasive particle laden air stream which is expelled outwardly through the end of the nozzle. When this abrasive particle laden air stream is directed so that it impinges upon the tooth structure, cutting of the tooth structure results.
Although such dental abrasive air systems have been known for many years, they have not enjoyed widespread use or acceptance for a number of different reasons. One reason for the commercial failure of these previously known dental air abrasive systems is that such systems create a "dusting" around the work area. While such abrasive particles are medically harmless, they do create an untidy and undesirable condition for the patient.
A still further disadvantage of these previously known dental air abrasive systems is that it was difficult to properly aim the effluent from the system nozzle. If improperly aimed, inadequate and imprecise cutting of the tooth structure can result or, alternatively, cutting of the wrong tooth structure and/or overcutting of the tooth structure.
A still further disadvantage of these previously known dental air abrasive systems is that typically only one size of abrasive material could be fed into the air stream. In practice, however, different types of abrasive materials and/or different sizes of abrasive materials are more desirable for different dental applications.